Anna-Lisa Waldemar runs an old boarding house on the beautiful island of Sunnanö in the Swedish archipelago together with her son Oscar and his family. Without Oscar's knowledge Anna-Lisa invites his brother Lasse and sister Jonna in time for the summer opening. Oscar's shock has barely sunk in before another shock shatters his world – Anna-Lisa is found dead and her last will stipulates certain conditions for the siblings: They have to run the boarding house together during the entire season – or else they won't inherit anything at all. It is the mother's last effort to reunite her children, but it is easier said than done. It will change their lives and uncover hidden truths and dark family secrets. They will confront their unsolved past and struggle with current emotions. They will all find out whether blood is thicker than water …